category_monthly_archives

<?php
/**
 * Get archives markup.
 * Customize wp-includes/general-template.php -> wp_get_archives
 * @param string|array $args Optional. Override defaults.
 * @return string|null String when retrieving, null when displaying.
 */
function shintotsushin_wp_get_archives( $args = '' ) {
	global $wp_query;
	global $wpdb;
	// Be used in category or single.
	if ( ! is_category() and ! is_single() ) {
		return;
	}
	// Get category id.
	$cat_id = (int) $wp_query->query_vars['cat'];
	// Set default parameter.
	$defaults = array(
		'type'            => 'monthly',
		'limit'           => '',
		'format'          => 'html',
		'before'          => '',
		'after'           => '',
		'show_post_count' => false,
		'echo'            => 1,
		'order'           => 'DESC',
	);
	// Crete parameter.
	$args = wp_parse_args( $args, $defaults );
	// Create where condition of sql.
	$type = ( '' === $args['type'] ) ? 'monthly' : $args['type'];
	$limit = '';
	if ( '' !== $args['limit'] ) {
		$limit = absint( $args['limit'] );
		$limit = ' LIMIT ' . $limit;
	}
	$order = strtoupper( $args['order'] );
	if ( 'ASC' !== $order ) {
		$order = 'DESC';
	}
	$where      = apply_filters(
		'getarchives_where',
		"WHERE post_type = 'post' AND post_status = 'publish' AND t.term_taxonomy_id = " . $cat_id,
		$args
	);
	$custom_sql = "LEFT JOIN $wpdb->term_relationships AS r ON $wpdb->posts.ID = r.object_ID LEFT JOIN $wpdb->term_taxonomy AS t ON r.term_taxonomy_id = t.term_taxonomy_id LEFT JOIN $wpdb->terms as terms ON t.term_id = terms.term_id";
	$join       = apply_filters( 'getarchives_join', $custom_sql, $args );
	// Set return markup
	$output = '';
	// Set cache
	$last_changed = wp_cache_get( 'last_changed', 'posts' );
	if ( ! $last_changed ) {
		$last_changed = microtime();
		wp_cache_set( 'last_changed', $last_changed, 'posts' );
	}
	// Create monthly category archives query.
	if ( 'monthly' === $type ) {
		$query = "SELECT YEAR(post_date) AS `year`, MONTH(post_date) AS `month`, count(ID) AS posts FROM $wpdb->posts $join $where GROUP BY YEAR(post_date), MONTH(post_date) ORDER BY post_date $order $limit";
		$key   = md5( $query );
		$key   = "wp_get_archives:$key:$last_changed";
		if ( ! $results = wp_cache_get( $key, 'posts' ) ) {
			$results = $wpdb->get_results( $query );
			wp_cache_set( $key, $results, 'posts' );
		}
		if ( ! empty( $results ) ) {
			$afterafter = $args['after'];
			foreach ( (array) $results as $result ) {
				$url   = shintotsushin_get_link( $result->year, $result->month, $cat_id );
				$text  = sprintf( __( '%2$d/%1$02d', 'cmarchives' ), $result->month, $result->year );
				$after = '';
				if ( $args['show_post_count'] ) {
					$after = '&nbsp;( ' . $result->posts . ')' . $afterafter;
				}
				$output .= get_archives_link( $url, $text, $args['format'], $args['before'], $after );
			}
		}
	}
	// Return monthly category arvhives.
	if ( ! empty( $args['echo'] ) ) {
		echo $output;
	} else {
		return $output;
	}
}

/**
 * Get link.
 * Refer wp-includes/link-template.php->get_month_link
 * @param bool|int $year False for current year. Integer of year.
 * @param bool|int $month False for current month. Integer of month.
 * @param int $cat_id Category ID.
 * @return string
 * @link http://wpdocs.sourceforge.jp/%E9%96%A2%E6%95%B0%E3%83%AA%E3%83%95%E3%82%A1%E3%83%AC%E3%83%B3%E3%82%B9/WP_Rewrite
 * @version 1.0.0
 * @since 1.0.0
 */
function shintotsushin_get_link( $year, $month, $cat_id ) {
	global $wp_rewrite;

	if ( empty( $year ) ) {
		$year = gmdate( 'Y', current_time( 'timestamp' ) );
	}
	if ( empty( $month ) ) {
		$month = gmdate( 'm', current_time( 'timestamp' ) );
	}
	// Get monthly link.
	$month_link = $wp_rewrite->get_month_permastruct();
	if ( ! empty( $month_link ) ) {
		$month_link = str_replace( '%year%', $year, $month_link );
		$month_link = str_replace( '%monthnum%', zeroise( intval( $month ), 2 ), $month_link );
		// Add category id to query parameter.
		return apply_filters(
			'month_link',
			home_url( user_trailingslashit( $month_link, 'month' ) ) . '?cat=' . (int) $cat_id,
			$year,
			$month
		);
	} else {
		return apply_filters(
			'month_link',
			home_url( '?m=' . $year . zeroise( $month, 2 ) . '&cat=' . (int) $cat_id ),
			$year,
			$month
		);
	}
}